The set contains 4 RCR123 rechargeable batteries and 1 2-bay charger. The charger is suitable for charging 2 batteries at the same time, which is suitable for charging the most common batteries used in flashlights, toys, remote controls, etc. This eliminates the need to use multiple different types of chargers, saving you money and space. The smart charger is actually two units that work independently, they automatically recognize the inserted batteries and the required charging method separately, and even charge different types at the same time. 16340 Lithium - ion 16650 Lithium - ion 18650 Lithium - ion RCR123 Lithium - ion 17760 Lithium - ion 14500 Lithium - ion AA Ni-MH / Ni-CD AAA Ni-MH / Ni-CD Features: charge level display automatic shutdown after 8 hours non-slip rubber soles Dimensions: 96 mm x 31 mm Charging current / voltage: 1000mA / 4.2V for Lithium-ion batteries (18650, 17670, 16340, 14500) 500mA / 1.47V for NiMH batteries (AA, AAA) Operates from a 220 Volt socket.